Tone arm trip mechanism for phonographs



Aug. 13, 1940- o. A. HoKANsoN 2,211,423

TONE ARM TRIP MEGHANISM FOR PHONOGRAPHS Filed July 18, l1938 2 sheets-sheet 1 Aug 13, 1940 ofA. HoKANsoN 2,211,423

TONE ARM TRIP MEGHANISM FRv PHONOGRAPHS Fil'ed July 18, y19:58 a sheets-sheet 2 Patented Aug. 13, 1940 UNITED STATES PATENT OFFICE 'roNE ARM 'nur MECHANISM PHoNoGRAPHs FOR Ohio

Application July 18, 1938, Serial No. 219,681

12 Claims.

This invention relates to certain new and useful improvements in the tone arm trip mechanisms of automatic phonographs for initiating the restoration of the tone arm and other parts of the instrument to initial or starting position at the completion of playing a record.

It has for one of its objects to provide a trip mechanism of this character which has been designed more particularly for use with phonograph records having either the spiral-lead-in or eccentric type of extension groove at the termination of the recording groove, and wherein the trip mechanism is actuated only by the inward stroke or movement of the tone arm effected by its stylus encountering such extension groove.

Another object of the invention is to provide a tone arm trip mechanism which is simple, compact and inexpensive in construction. and which is positive and reliable in operation and not liable to get out of order.

Other features of the invention reside in the construction and arrangement of parts hereinafter described and particularly pointed out in the appended claims.

In the` accompanying drawings: y

Figure 1 is a fragmentary perspective view of an automatic phonograph mechanism showing my improved tone arm trip mechanism associated therewith. Figure 2 is a side elevation of the trip mechanism with the parts in their normal latched or record-playing position. Figure 3 is a top plan view of the same. Figure 4 is a view similar to Figure 2 but showing the parts in tripped or unlatched position after the playing of a record. Figure 5 is a detached, separated perspective view of the latch bar and trip member of the mechanism. Figure 6 is a vfragmentary perspective view of a modification of the latch bar and trip member. Figure '7 is a fragmentary perspective view of the clutch mechanism.

Similar characters of reference indicate corresponding parts throughout the several views.

By way of example, my invention has been shown in connection with an automatic phonograph of the multi-selective type, I indicating the platform or supporting frame of the phonograph chassis, II the turntable, I2 the tone arm or reproducer assembly mounted on an upright post I3 for lateral swinging movement over the turntable. As shown in Figure 1, each record I4 may be carried by a companion horizontally-swinging record tray I5 which is adapted to be selectively swung from a stack position at one side of the turntable to an operative position over the turntable for playing the record in the manner shown in the Wilcox Patent No. 2,002,236, dated May 21, 1935. A verticallyadjustable selector yoke I6 is adapted for coupling engagement with one or another of the record trays to selectively swing it from the carrier-stack to a position over the turntable and this swinging of the yoke is effected through the medium of a lever Il operated by a cam I8 mounted on a driven cam or operating shaft I9 and connected at its upper end by a link 20 with such yoke. A suitable clutch, such as that shown in Figure 7, and consisting of a shiftable clutch member 2| applied to the cam shaft I9 and having a spring 2I acting thereon for constantly urging it against the driven clutch member 2lb, controls the rotation of the cam shaft, the clutch being released during the playing of a record and being engaged to rotate the cam shaft and restore the record-changing mechanism including the carriers I5 as well as the tone arm to initial position. A clutch-actuating lever 22 cooperating with the shiftable clutch member is fixed 0n an oscillatory shaft 23 having a radial rod 24 projecting therefrom in operative relation with a lug 25 formed on an actuating arm 26 pivoted to said shaft and having a spring 2l applied thereto for urging it in a direction to bring its lug 25 in abutting engagement with the rod 24. At its upper end the arm 26 has a tooth-like projection 28 which is adapted to be latched to my tone arm trip mechanism indicated generally by the numeral 29. The spring 21 is connected at its lower end to an L-shaped lever 30 pivoted to the oscillating shaft 23 and engageable with a pin 3| projecting from a cam 32 applied to the shaft I9. In the playing posi- I tion of the phonograph, the clutch 2|, 2lb is disengaged and the cam-pin 3I holds the arm 26 in a position to place the spring 21 under tension, so that when the record has completed its play, the tone arm trip mechanism is rendered operative to release it from latched engagement with the arm-tooth 28, whereupon said spring actuates the arm 26 in a direction to rock the shaft 23 and shift the clutch-actuating lever 22 to a position to effect the automatic engagement of the clutch member 2I with the companion member 2lb, and thereupon the restoration of the record-changing mechanism, as well as the tone arm, to initial position.

My improved tone arm trip mechanism is adapted for actuation by the customary center record-extension grooves of the spiral-lead-in or eccentric type and is designed to function or be tripped after the record has been played solely by an in-movement of the tone arm. In the spiral-lead-in type of groove the tone. arm is swung smartly inward to operate the trip mechanism, and in the eccentric type of extension groove the tone arm is oscillated in and out and at a given time during an inward stroke of such oscillating action operates the trip mechanism to unlatch it from the actuating arm 26. This trip mechanism is preferably constructed as follows:

Mounted on a depending support or framepiece 33 of the phonograph chassis for releasable l5 latching engagement with the actuating arm 26 is a vertically-swinging latch bar or dog 34 pivoted intermediate its ends at 35 and provided at its outer end with an inwardly-facing shoulder 36 for retaining engagement with the tooth 28lon the actuating arm and which arm governs or initiates the restoring movements of the phonograph parts to starting position alter a record has been played. Coaxially pivoted to swing with the latch bar, and adapted for independent linear or longitudinal adjustment relative to the latter in seeking a tripping position, is a trip member 31 which is disposed alongside the latch bar, being pivotally supported )intermediate its ends on the pivot 35 through a slot 38 and having a screw and slot connection 39, 40 at its inner end with the latch bar, whereby to guide the trip member longitudinally of the latter and yet compel its pivotal movement with such latch bar. On the upper side of its inner end the trip member 31 has an inclined trip lug or flange 4| with which a tappet lug 42, formed on a tappet arm 43 secured to the tone arm post I3, is adapted to engage on the inmovcment of the tone arm to rock the trip member and latch bar downwardly to a released or unlatched position. v

Inwardly of this trip lug 4I and in the upper edge thereof, the trip member 31 has a longitudinal row of upright ratchet teeth 44 with which a pivoted feed pawl 45 borne by the tappet arm 43 engages and functions to advance the trip member step by step to a trip-seeking position during the oscillations of the tone arm after its stylus encounters an eccentric type of extension groove. The opposite end of the trip member has a laterally-bent flange 46 overhanging the adjoining edge of the latch bar 34 and such ange has a longitudinal row of horizontal ratchet teeth 41 therein with which an escapement pawl 48 is adapted to engage, such pawl being mounted on a lateral extension 49 of the support 33. A spring 50 connected at one end to a depending lug 5I of the trip member 31 and at its other end to an adjoining part of the phonograph chassis serves to resist movement of the trip member and latch bar out of normal latched position and further to constantly urge the trip member longitudinally inwardly or in a direction wherein its connecting slots 38, 40 abut at their outer or left hand ends (viewing Figure 1) against the pivot 35 `and screw 39, respectively. In this position of the trip mechanism, the pawl 48 clears the outer end of the flanged-tooth portion 46 of the trip member as it likewise does after a tripping operation, so that during the return swinging movement of the trip member and latch bar this pawl 48 will not interfere with the restoration of these parts to their initial set position. During the travel of the feed pawl 45 over the inclined portions of the ratchet teeth 44, the companion pawl 48 retains the trip member 31 in respective adjusted positions against longitudinal displacement by the spring 5D'and for this purpose the flange-teeth 41 thereof are preferably of less pitch and more in number than the teeth 44.

Should it be desired to eect a manual tripping of the trip mechanism, I provide a stationary tappet 52 properly disposed in the path of longitudinal travel of the inclined lug 4l of the trip member 31, so that when the tone arm I3 is picked up and swung outwardly the trip member will be shifted longitudinally outwardly because of the ratchet and pawl connection 44, 45, and when its trip lug encounters the tappet 52 the trip member and latch bar 34 will be rocked downwardly about their common pivot 35 to unlatch the actuating arm 26.

In the modification of the trip mechanism shown in Figure 6, the latched bar 53 and trip member 54, are substantially identical with the corresponding members heretofore described, but in this form of the invention the inward displacement of the trip member is prevented by an escapement pawl 55 pivoted to the outer end of the latch bar and disposed for engagement with a row of ratchet teeth 56 applied to the lower edge of the tail end of the trip member 53. A spring 51 attached to this pawl constantly urges it into engagement with the ratchet teeth. This pawl has a depending tail 58 which is disposed in the path of movement of the tooth 28 of the actuating arm 26 so that when the actuating arm is released, due to a tripping of the trip mechanism, said tooth encounters the pawl-tail and holds the pawl out of engagement with the companion ratchet teeth 56. When the trip mechanism and the actuating arm 26 are restored to their initial position, the escapement pawl 55 is urged toward the lower edge of the ratchet tooth end of the trip member.

In operation, when the tone arm reaches the extension groove at the termination of the playing groove of the record, assuming the extension groove to be the spiral-lead-in type, the tappet lug 42 encounters the inclined trip lug 4I on the trip member 31 during the in-swing of the tone arm, to thereby rock the trip member downwardly and unlatch it from the arm 26. Immediately upon completion of this tripping action, the spring 5D restores the latch bar 34 and the trip member 31 to their initial position, and during this movement it also forces the trip member to the right to its normal position. When the trip member is shifted to its normal position, and its flanged end 46 swung downwardly, such end bearing the horizontally-disposed ratchet teeth 41 is positioned clear of the cooperating pawl 48 so that there is no interference in this restoring movement of the parts. When an eccentric type of lead-in groove is encountered by the tone arm needle, the pawl 45 ratchets over the teeth 44 of the trip member 31 and gradually forces such lever to the left, and the pawl 48 cooperates with the ratchet teeth 41 to hold the trip member in such feed position. At a predetermined time during the oscillating movements of the tone arm, the tappet lug 42, on an in-movement of the tone arm, encounters the inclined trip lug 4I on the trip member and causes the latter to rock downwardly to release it from latched engagement with the actuating arm 26.

I claim as my invention:

1. In an automatic phonograph, a tone arm for playing records having extension grooves of either the spiral-lead-in or eccentric type, a releasable actuating means including operative connections with the tone arm for initiating its restoration to initial position after playing a record, a pivoted latch bar normally latched with said actuating means, and trip means operatively connected to said latch bar and in cooperative relation with said tone arm for pivoting the latch bar from -latching engagement with said actuating means only during an inward travel of such arm in the record extension-grooves of either of the aforesaid types, said trip means including a trip member pivoted alongside the latch bar for movement therewith into and out of latching position and for linear movement thereto in seeking a tripping position, and means movable with the tone arm and engageable at a predetermined time with the trip member for advancing it to trip-seeking position and at a subsequent time engageable with said trip member on an in-movement of the tone arm ln the center extension groove of the record for jointly pivoting said latch and trip members to an unlatching position.

2. In an automatic phonograph, a tone arm assembly pivoted to swing laterally for playing records having extension grooves of either the spiral-lead-in or eccentric type, the tone arm assembly swinging smartly inward when its stylus encounters a spiral-lead-in-groove type of record and oscillating in and out when its stylus encounters an eccentric-groove type of record, a releasable actuating member for initiating the restoration of the tone arm to its initial outward position after playing a record, a shiftable latch bar latched with said actuating member during the playing of a record, and trip means for shifting the latch bar from latching engagement with said tone arm assembly restoring member after the playing of a record, said trip means including a trip member operatively connected to said latch bar for movement relative thereto to a tripseeking position and tappet and pawl members operatively connected with the tone arm assembly to move therewith, said pawl being engageable with the trip member during oscillating movements of the tone arm for shifting said trip member to a trip-seeking position toward said tappet, the latter actuating said trip member and latch bar to released position either during a smart inward movement of the tone arm assembly or during an inward stroke of the oscillating in and out movement of such tone arm assembly.

3. In an automatic phonograph, a tone arm assembly pivoted to swing laterally for playing records having extension grooves of either the spiral-lead-in or eccentric type, the tone arm assembly swinging smartly inward When its stylus encounters a spiral-lead-in-groove type of record and oscillating in and out when its stylus encounters an eccentric-groove type of record, a releasable actuating member for initiating the restoration of the tone arm to its initial outward position after playing a record, a shiftable latch bar latched with said restoring member during the playing of a record, and trip means for shifting the latch bar from latching engagement with said tone arm assembly restoring member after the playing of a record, said trip means including a trip member operatively connected to said latch bar to move therewith to and from a latching position and free to move relatively to the latch bar in seeking a tripping position, said trip member having a row of ratchet teeth thereon, and a cooperating tappet disposed in the operating path of said latch trip member in seeking a tripping position and having a pawl thereon engageable With the ratchet teeth of the trip member to advance the latter to a tripping position, said tappet and companion pawl being operatively connected with the tone arm assembly to move therewith for actuating said trip member and latch bar to released position either during a smart inward movement of the tone arm assembly or during an inward stroke of the oscillating in and out movement of such assembly subsequent to the pawl advancing the trip member in step by step fashion to a position in opera... tive tripping relation with said tappet.

4. In an automatic phonograph, a tone arm assembly for playing records having extension grooves of either the spiral-lead-in or eccentric type, a releasable actuating member including operative connections to the tone arm assembly for initiating its restoration to initial position after playing a record, a pivoted latch bar normally latched with said releasable actuating member, a coaxially pivoted trip member having connections between it and said latch bar for compelling a joint pivotal movement of such parts into and out of latching position and permitting an independent, adjustable linear movement of the trip member relative to the latch bar in seeking a tripping position, means applied to the tone arm assembly and operatively connected with said trip member for advancing it to a predetermined tripping position in response to the tone arm movements on its entering the extension groove of the record, and tappet means connected with the tone arm assembly to move therewith into tripping engagement with said trip member on an in-movement of the tone arm in the record-extension-groove.

5. In an automatic phonograph, a tone arm assembly for playing records having extension grooves of either the spiral-lead-in or eccentric type, a releasable actuating member including operative connections to the tone arm assembly for initiating its restoration to initial position after playing a record, a pivoted latch bar normally latched with said releasable actuating member, a coaxially pivoted trip member having connections between it and said latch bar for compelling a joint pivotal movement of such parts into and out of latching position and permitting an independent, adjustable linear movement of the trip member relative to the latch bar in seeking a tripping position, means applied to the tone arm assembly and operatively connected with said trip member for advancing it to a predetermined tripping position in response to the tone arm movements on its entering the extension groove of the record, means for yieldingly urging the latch bar and trip member jointly to a latching position and said trip member in a direction opposite to its tripseeking position, escapement means cooperating with said trip member for releasably retaining the latter in advancing positions of linear adjustment, and tappet meansconnected with the tone arm assembly to move therewith into tripping engagement with said trip member on an in-movement of the tone arm in the record-extension-groove.

6. A tone arm trip assembly for initiating the movement of a phonograph mechanism to starting position after playing records having extension grooves of either the spiral-lead-in or eccentric type, comprising a pivoted latch bar adapted for releasably latching an actuatable part of the phonograph mechanism in a normal position, a coaxially pivoted trip member having connections between it and said latch bar for compelling a joint pivotal movement of such parts into and out of latching position and permitting an adjustable linear movement of the trip member relative to the latch-bar in seeking a tripping position, and means adapted for movement with the tone arm and operatively engageable with said trip member to adjust it to a position to effect its tripping and to cause the pivoting of the latch'bar to unlatched position on an in-rnovement of the tone arm in the-record-extension groove.

'7. A tone arm trip assembly for initiating the movement of a phonograph mechanism to starting position after playing records having extension grooves of either the spiral-lead-in or eccentric type, comprising a pivoted latch bar adapted for releasably latching an actuatable part of the phonograph mechanism in a normal position, a coaxially pivoted trip member having connections between it and said latch bar for compelling a joint pivotal movement of such parts into and out of latching position and permitting an adjustable linear movement of the trip member relative to the latch-bar in seeking a tripping position, a spring connected to said trip member for yieldingly resisting movement of it and the latch bar out of a normal latched position and for yieldingly resisting linear movement of the trip member to trip-seeking position, and means adapted for movement with the tone arm and operatively engageable with said trip member to adjust it to a position to eiect its tripping and to cause the pivoting of the latch bar to unlatched position on an in-movement of the tone arm in the record-extension groove.

8. A tone arm trip assembly for initiating the movement of a phonograph mechanism to starting position after playing records having extension grooves of either the spiral-lead-in or eccentric type, comprising a pivoted latch bar adapted for releasably latching an actuatable part of the phonograph mechanism in a normal position, a coaxially pivoted, trip member having ratchet teeth thereon disposed alongside said latch bar and having connections therebetween for compelling a joint pivotal movement of such parts into and out of latching position and permitting a linear movement of the trip member relative to the latch bar in seeking a tripping position, a pawl adapted for attachment to the tone arm and engageable with the ratchet teeth of the trip member for advancing itv to a trip seeking position during an out-movement of the tone arm when encountering an eccentric type of eccentric groove, and a tappet adapted for attachment with the tone arm and engageable with said trip member for rocking it and the latch bar to an unlatched position on an inmovement of the tone arm when encountering either type of extension groove.

9. A tone arm trip assembly for initiating the movement of a phonograph mechanism to starting position after playing records having extension grooves of either the spiral-lead-in or eccentric type, comprising a pivoted latch bar adapted for reieasably latching an actuatable part of the phonograph mechanism in a normal position, a coaxially pivoted, trip member having ratchet teeth thereon disposed alongside said latch bar and having connections therebetween for compelling a. joint pivotal movement of such parts into and out of latching position and permitting a linear movement of the trip member relative to the latch bar in seeking a tripping position, a pawl adapted for attachment to the tone arm and engageable with the ratchet teeth of the trip member for advancing it to a trip seeking position during an out-movement of the tone arm when encountering an eccentric type of eccentric groove, a tappet adapted for attachment with the tone arm and engageable with said trip member for rocking it and the latch bar to an unlatched position on an in-movement of the tone arm when encountering either type of extension groove, and yieldablemeans -connected to said trip member for restoring it to its initial ratcheting position and both the trip member and latch bar to latch-assuming position after the tripping operation.

10. A tone arm trip mechanism for phonographs, comprising adjoining, pivoted latching and trip members having connections therebetween for compelling a joint pivotal movement of such members into and out of latching position and permitting a linear movement of the trip member relative to the latching member, said trip member having ratchet teeth thereon, and means adapted for movement with the tone arm and including a pawl engageable with the ratchet teeth of the trip member for advancing it to a trip-seeking position relative to the latching member and a tappet engageable with said trip member on an in-movement of the tone arm in the center extension groove of the record for pivoting said members to an unlatched position.

11. A tone arm trip mechanism for phonographs, comprising adjoining, pivoted latching and trip members having connections therebetween for compelling a joint pivotal movement of such members into and out of latching position and permitting a linear movement oi the trip member relative to the latching member, said trip member having two rows of ratchet teeth thereon, means adapted for movement with the tone arm and including a feed pawl engageable with one of said rows of ratchet teeth for advancing the trip member to a trip-seeking position relative to the latching member and a tappet engageable with said trip member on an inmovement of the tone arm in the center extension groove of the record for pivoting said members to unlatched position, an escapement pawl engageable with the other row of trip member ratchet teeth, and means connected to one of said members for yieldingly resisting their relative linear and joint pivotal movement to trip-seeking and unlatching positions, respectively.

12. A tone arm trip mechanism for phonographs, comprising adjoining, pivoted latching and trip members having connections therebetween for compelling a joint pivotal movement of such members into and out of latching position and permitting a linear movement of the trip member relative to the latching member, said trip member having ratchet teeth thereon, means adapted for movement with the tone arm and including a pawl engageable with theratchet teeth of the trip member for advancing it to a trip-seeking position relative to the latching member and a tappet engageable with said trip member on an in-movement of the tone arm in the center extension groove of the record for pivoting said members to an unlatched position, and a stationary tappet disposed in the tripseeking path of travel of the trip member for engagement therewith to pivot said members to unlatched position upon a manual outward swing of the tone arm.

O'I'IO A. HOKANSON. 

